Sharing the Vista way

1) Right-click on a folder, click "Share...".
2) Add "Everyone" to the list.
3) Set "Everyone" to either, "Reader", "Contributor", or "Co-owner", depending on your preference.
4) Click the button, "Share".
5) Click "Continue".
6) Click "Done".

If you did this in the XP way (Advanced Sharing), afterwards, you still have to run through "Sharing the vista way", without doing #2 and #3.